Roll clamp for lift truck and method



Jan- 7, 1969 R. l.. MESSINGER ROLL CLAMP FOR LIFT TRUCK AND METHOD FiledFeb. 1o, 1967 Sheet INVNTOR. M55/N65? u* l y fx y R. L.. MESSINGER ROLLCLAMP FOR LIFT TRUCK AND METHOD Jan. 7, 1969 Sheet 2 of2 Filed Feb. l0.1967 I N VENTOR. /Qof/er l. /Wfss/fveff? roA/fys United States Patent O3,420,565 ROLL CLAMP FOR LIFT TRUCK AND METHOD Robert L. Messinger,Langhorne, Pa., assignor to Eaton Yale & Towne Inc., Cleveland, Ohio, acorporation of Ohio Filed Feb. 10, 1967, Ser. No. 615,259 U.S. Cl.294-86 Int. Cl. B66f 9/18; B66c l/10 9 Claims ABSTRACT OF THE DISCLOSUREA roll clamp having linearly movable arms. One f the 'arms is pivotedand can be positively locked in either of two positions for manipulatingrolls as by pushing, as well as for lifting rolls of differentdiameters.

The problem In the lifting and handling of large rolls of sheetmaterial, as for example rolls of paper and the like, it is oftendesirable to push or otherwise manipulate a roll, as ywell 'as to graspit for lifting purposes. Thus, a roll is grasped, lifted and moved; and,then it is pushed firmly into a confined space for most efficientstorage.

Knowledge of the pertinent prior art indicates that while the clampinganms and jaws of roll clamping apparatus for industrial lift trucks havebeen movable for grasping and lifting purposes, they have not beencapable of being positively locked in p-lace for pushing and likemanipulation purposes.

Also, knowledge of the prior art indicates that the width of the clampexceeds the normal width of the body of the truck to which it isattached. This is 'a su-bstantial hindrance to the flexibility of thetruck, because it limits the trucks ability to get into and out of tightplaces to pick up and place a roll.

It is, therefore, obvious that a substantial advance to the art would'be provided by a novel roll clamp for an industrial lift truck, whereinthe pivoted arm could be locked in positions for manipulating rolls, sothat it would have much greater ilexibility of use than simply graspingand lifting.

It is also evident that a substantial advance to the art would beprovided by a novel roll clamp wherein the clamping arms are movable byhydraulic rams and further that movement and locking of the linearly andpivotally movable arm is effected automatically and simultaneously uponactuation of its hydraulic ram.

It is also evident that a substantial advance to the art would beprovided by a novel roll clamp wherein the width of the clamping arms ismaintained within the normal width of the body of the lift truck.

Objects of the invention are, therefore, to provide a novel r-oll clampfor an industrial lift truck embodying the foregoing features.

Of course, in addition to the foregoing, it is desirable for `anindustrial lift truck roll clamp of the class herein contemplated, to beable to handle a wide range of diameters of rolls. This is alsoaccomplished by the present invention by adapting both of the arms forlinear movement toward and' away 4from one another; and, further byadapting one of the clamping arms for pivotal movement relative to theother arm. By this arrangement, a wide range of roll sizes. isaccommodated by a relatively Vice short linear movement of either of thearms. This provides a very compact and sturdy structure and makespossible the use of relatively short and, thus, strong hydraulicactuating rams for moving the grasping arms.

Another Ifeat-ure of the invention that will become evident as thisdescription progresses is that the roll clamp is adapted to pick uprolls lying horizontally. Thus, the linearly and pivotally movable armis made of greater length than the short anm which is linearly movableonly, so that it can reach over a roll lying horizontally. Thus, theshorter, linearly movable arm is positioned beneath the roll at a pointnear its contact with the floor; and, the longer arm contacts the top ofthe roll at a point substantially diametrically opposite the lowercontact point. This steadies the roll and effectively holds it withint'he arms to grasp the roll for pick up.

As regards picking up a roll that is standing on end, the operator ofthe truck merely jockeys the ends of the arms into correct position andmoves them together in a grasping fashion to hold the roll for movement.

A further feature of the invention that will become evident as thedescription progresses is that the clamp is rotatable about a horizontalaxis. Thus, rolls may be gripped while standing on end and then rotatedto be laid down, or may be rotated and thereby turned end for end.Further, rolls may be gripped while lying down on their side and thenturned 90 to be stood on end, or rotated 180 and thus turned end forend. Thus, a roll can be gripped and picked up from substantially anyposition and also placed in substantially any position.

A still further feature of the invention is that each clamping arm isprovided at the free end with a pivotally movable gripping jaw thatautomatically embraces the surface of a roll in an improved, graspingfashion.

I have thus outlined the general nature of my invention and its relationto the prior art in order that the description thereof that follows maybe better understood, and in order that my contributions to the art maybe better appreciated. There are, of course, additional features of myinvention that will be described hereinafter and which will form thesubject lmatter of the claims appended hereto. Those skilled in the artwill appreciate that the conception upon which my disclosure is basedmay be readily utilized as the basis for the designing of otherstructures for carrying out the several purposes of the invention. It isimportant, therefore, that the claims granted to me sh'all be construedsuiciently broadly 'to prevent the appropriation of my invention byothers skilled in the art.

Referring now to the drawings:

FIGURE l is a front-elevational view of the entire clamping mechanism ofinvention with the jaws positioned horizontally and for vertical spread;and

FIGURE 2 is a side-elevational view of FIGURE 1.

Referring now to the drawings, the reference numeral 10 represents theroll clamp of the present invention. A hanger block 12, shown at theleft side of FIGURE 2', an angle mount'14 and a lower clip 16 make uppart of the standard mechanism of the lift truck, not shown, forattaching the invention to the front end of the truck. These elementsform no part of the present invention, and therefore, are shown anddescribed only generally. The attachmet mechanism also includes arotating mechanism, indicated generally by the reference numeral 18.This includes a horizontally oriented pivot shaft 20 upon which theinvention is mounted for rotation at the will of the operator throughthe control and power provided by the rotating mechanism 18.

It will be understood, therefore, that the invention is adapted to bepivotally mounted on the lift truck and, if desired, may be lifted andlowered by mechanism carried by the truck, such as hydraulic lift rams.

Additionally, however, as will become evident, the jaw carrying arms 22and 24 can be moved toward and away from one another for grasping andmanipulating purposes by their own control arms.

The roll clamp includes a frame comprising a rotatable front plate 26supported by the rotatable pivot shaft 20, FIGURE 2. A body subassembly28 is secured to the -rotatable front plate 26 by means of cross plates30, FIGURES l and 2. As best shown in FIGURE l, the body subassembly 28includes a rst pair of lineal guideways 32 on which are slidable a firstpair of complementary guideways 34 which in turn support the lower orshort gripper arm 22.

The body subassembly 28 also includes a second pair of guideways 36 onwhich is slidable a pair of complementary guideways 38 which in turnsupport the upper or longer gripper arm 24 of the roll clamp ofinvention.

A rst hydraulic rarn 40 is employed to manipulate the gripper arm 22 anda second hydraulic ram 42 is employed to manipulate the longer gripperarm 24. The first ram 40 has the cylinder head end 44 fastened to theupper cross plate by bolting at 46. The exposed end of the piston rod 48is connected to the central portion of the arm assembly 22 by bolting at50.

The second ram 42 has the cylinder head end 52 fastened to the lowercross plate 30 by bolting at 54. The exposed end of the piston rod 56 isconnected to the central portion of the arm assembly 24 by bolting at58.

By application of pressurized hydraulic fluid from hydraulic circuitmeans, not shown, the gripper arms 22 and 24 can thereby be movedlinearly relative to one another for grasping and manipulating purposesin a particular manner that will become evident as this descriptionprogresses.

The lower or shorter clamping arm 22, in detail As best shown in FIGURE2 the clamping arm assembly 22 includes an L-shaped support plate 60that is welded at upper and lower points 62 to each of the firstcomplementary guideways 24. The piston rod 48 of ram is secured to aconnecting plate assembly 64 and thus to the central portion of theL-shaped support plate 60. The L-shaped support plate includes avertical plate portion 66 that is formed integrally with a horizontalplate portion 68. An arcuate or curved clamping plate 70 has the upperedge welded at 62 to the upper edge of the vertical plate portion 66.The lower, outer edge 72 of plate 70 is welded at 74 to the outer end ofthe horizontal plate portion 68. This provides a compact, stiff andstrong, generally triangular Weldment.

Vertical movement of the clamping arm assembly 22 between the solid lineposition and the dotted line position by means of the first ram 40 isindicated in FIGURE 2. It is to be noted that it can be dropped belowfloor line, if desired. This will take place when the unit is pivotedfor spreading the arms to grasp a larger roll.

At the outer end of the horizontal plate portion 68, there is a pivotedjaw 78. Each of the plates 68 and the jaw 78 has aligned pivot sleeves80, attached by welding, and a pivot pin 82 is passed through andsecured as by an appropriate cross pin or set screw, not shown.

The jaw 78 is automatically pivoted to a desired gripping orientation bycontact with a roll, and is returned to a neutral position by means of acontrol spring 84. A yoke 86 is fastened to a median portion of thehorizontal plate portion 68 and has a hole 88 through which the backhook end Vof the spring 84 is passed. The forward end of spring S4 has aloop end 90 and receives the back hook end 92 of a connecting rod 94.The forward end of the connecting rod 94 is pivotally connected at 96 tothe underneath side of the lower jaw 78.

The upper or longer clamping arm 24, in detail As also shown moreclearly in FIGURE 2, the clamping arm assembly 24 includes an armcarrier Weldment 4 98. Weldment 98 includes spaced plate means 100, alsoshown in FIGURE 2, bridged by an upper spacer plate 102 and a lowerspacer plate 104 which provide a rigid box-like structure. By means of avertical cross plate 106, best shown in FIGURE 2, the upper spacer plate102 and the spacer plate 104, the carrier Weldment 98 is fastened to thesecond complementary guideways 38, FIGURE l, for linear movementthereon.

The piston rod 56 of ram 42 is secured to a cross plate 108, FIGURE 2and thus to the central portion of the carrier Weldment 98.

The swinging arm assembly 24 comprises a swinging arm Weldment 110 thatincludes spaced arms 112, fabricated from plate stock, that arepivotally mounted to the arm carrier Weldment 98 by cross shaft 114. Thecross shaft 114 is supported in the spaced plate means 100 byappropriate, aligned holes therein; and, the spaced arms 112 also eachincludes a hole to receive the shaft 114. A washer 116 and a suitableretainer cross pin at each end completes the assembly.

Extending between each of the spaced arms 112, to complete the Weldment110, is an outer plate 118 and an inner plaie 120, welded in place forpurposes of stiffening the spaced arms as a box-like Weldment. The outerplate 118 extends out beyond the inner plate 120 as best shown in FIGURE2.

Vertical movement of the clamping arm assembly 24 between the solid lineposition and the dotted line position by means of the second hydraulicram 42 is indicated in FIGURE 2. The particular manner in which thesimultaneous pivoting action is also accomplished will be made evidentas the description continues.

At the outer end of the swinging arm Weldment 110, there is an upperpivoted jaw 79. Each of the outer plate 118 and the jaw 79 has alignedpivot sleeves 80, attached as by welding, and a pivot pin 82 is passedthrough and secured as by an appropriate cross pin or set screw, notshown.

The jaw 79 is automatically pivoted to a desired gripping orientation bycontact with the surface of a roll, and is returned to a neutralposition by means of a control spring 8S. A yoke 87 is fastened to amedian portion of the upper plate 118 and has a hole 88 through whichthe back hook end of spring 8S is passed. The forward end of spring 8Shas a hoop end 90 and receives the back hook end 92 of a connecting rod95. The forward end of the connecting rod is pivotally connected at 96to the underneath side of the upper jaw 79.

The pivoting mejzanism for the upper clamping arm 24, in detail As setforth in the introductory portion of this specification, it is a purposeof the invention to lock the upper or longer arm 24 in either of twopositions so that the arm can be used to push and otherwise manipulate aroll of material. This is accomplished by the present invention in twoways:

(l) By latch and stop means at the top position; and,

(2) By cam means at the bottom position.

The latch and stop means As best shown in FIGURE 2, a latch arm 122 ispivotally mounted to each plate of the arm carrier weldment 98. For thispurpose, as shown in FIGURE l, a pivot stub shaft 124 extends outwardlyfrom each plate 100. Each latch arm 122, as shown in FIGURE 2, has thebottom end journaled on the pivot stub shaft 124.

The latch arm 122 includes a latch notch 126 at the top and the spacedarms 112 each carry a latch pin 128, which is located to fall into thenotch 126 when the several parts swing to a position for such action totake place.

Each latch arm element 122 also includes a cam surface 130 whosefunction in cocking the latch 122 back to a retracted position so thatthe notch 126 clears the pin 128, will be brought out below.

A latch return spring 132 is effective to pull the latch arm 122 to aholding position when the latch is in `a position to be so moved. Eachlatch arm 122 has a spring hook plate 134, best shown in FIGURE l, witha hole 136 to receive the hook end of the latch return spring 132. Atthe other end, the spring 132 is hooked to a rod element 138, best shownin FIGURE 2, fastened to the arm carrier weldment 98.

Beneath the rear end of each of the spaced arms 112 of the swinging armweldment 110, there is a stop block 140. The stop block 140 is fastenedto the outside of each plate 160 in engageable alignment with an arm112. Each stop block 140 carries a set screw 142 and lock nut 144 foradjusing the stop position of an arm 112.

The latch arm 122 holds the swinging arm weldment 110 against clockwiserotation in the upper solid line position. The adjustable set screw 142of the stop block 140 holds the arm weldment 110 againstcounterclockwise rotation.

An arrangement of par's wherein the latch arm and Stop block provideopposite anti-rotation is to be encompassed within the scope of theinvention.

Each of the spaced arms 112 also carries a cam roller follower 146 whichis engageable with a cam track 148 now to be described. It will beexplained that the swinging arm weldment 110 is moved verticallydownwardly from the solid line position by the second hydraulic ram 42.As it is so moved, the cam surface 130 on the latch 122 is moved by anabutment and releases the latch arm from the latch pin 128; and, the camtrack 148 produces the pivoting action indicated. Additionally, asdistinguished from the prior art of present knowledge, the cam track 148is effective to positively lock the upper arm 24 in the dotted lineposition for both positive manipulating as by pushing, and also forpositive grasping for lifting purposes.

The cam track 148 is formed in a block of steel 150, fastened to theoutside of the body subassembly 28. A steel block 150 and track 148 isprovided at each side as shown in FIGURE l. Since the subassembly 28 isxed relaiive to the movable arms 22 and 24, the cam track 148 is heldfast.

It will be noted that the cam track comprises a straight or verticalportion 152 and a sharply cut-back portion 154. The cut-back portion 154functions as the locking portion.

Operation of the invention; downward movement from the solid lineposition of FIGURE 2 to the dotted line position As the second hydraulicram 42, FIGURE l, is called upon to move the upper arm 24 down from thesolid line position of FIGURE 2, the ca m surface 130 of the latch arm122 engages the upper, outer corner 156 of the steel cam block 150. Thiscocks the latch arm 122 forward and releases the latch notch 126 fromthe latch holding pin 12S. The arm 24 is then free to pivot. However,the arm 24 does not pivot at the instant of latch release because thecam roller 146 has entered the straight portion 152 of the cam track148. This holds the arm in the same attitude as shown in solid outlinein FIGURE 2. However, subsequently when the cam follower roller 146enters the sharply cut-back portion 154 of the track 148, the arm 24pivots downwardly to assume the attitude of the dotted line positionshown in FIGURE 2. Simultaneously, the arm 24 is locked in this dottedline attitude by the cut-back portion 154.

Upward` movement of the upper arm 24 from the dotted line position ofFIGURE 2 back tothe solid line position As the second hydraulic ram 42,FIGURE 1, is called upon to move the upper arm 24 upwardly from thedotted line position, a sequence of events takes place. First, thesharply cut-back cam surface 154 initially pivots the arm up to theattitude of the solid line position, causing engagement between the backof the cam and the stop block Set screw 142. However, it is not yet atthe actual top solid line position shown. This initial pivoting releasesthe lower lock condition and places the latch pin 128 in lockingattitude.

Subsequent linear movement of the arm 24 places the cam follower roller146 in the straight track portion 152 and, as it continues to move up,the cam surface 130 of the latch 122 moves past the upper corner 156 ofthe cam block 150. The spring 132 causes the latch notch 126 to droponto the latch pin 128. Thus, after unlocking and pivoting have takenplace, followed by some linear movement, locking the arm 24 in the solidline attitude then takes place. However, the arm 24 is still not yet atthe position shown in the solid line of FIGURE 2.

Subsequent linear movement of the second ram 42 is effective, however,to place the arm 24 back at the solid line position.

The sequence, therefore, comprises the following steps:

(l) Unlocking the arm by movement out of the cutback cam portion, andsimultaneously pivoting the arm upwardly or outwardly as the case may beso that the bottom of the arm abuts the stop block;

(2) Linearly moving the arm, thereby permitting the cam portion of thelatch to release the latch notch into engaging relationship with thelatch pin; and,

(3) Then, linearly moving the arm to the end of its linear path toassume the solid line position shown.

SUMMARY An important advantage of the invention is that while the armsmay be used to push a roll of material, the width of the clamp neverexceeds the normal width of the body of the truck to which it ismounted.

A further important advantage of the invention is that the pivoted armis positively locked in each of its two operating positions.

A further important advantage of the invention is that when the arm ismoved from one to the other of its positions, or vice versa, it isautomatically positively locked in the position to which moved and thistakes place without attention on the part of the truck operator.

Thus, the contribution of the present invention to the art resides inthe feature that the pivotal arm is always rigid and is alwayspositively held in an active position for grasping as well as otherwisemanipulating a roll; and, movement between positions is automaticallycontributed as the arm moves from one position to the other.

I believe that the considerable merits and the greater simplicity of myinvention will now be understood and appreciated by those skilled in theart.

I claim:

1. In a roll clamp of the class described:

a frame having first linear guide means thereon,

a first grasping arm carried by said first linear guide means and meansfor linearly moving said first grasping arm along said first linearguide means,

second linear guide means on said frame,

an arm carrier, and means for linearly moving said arm carrier alongsaid second linear guide means,

a second grasping arm pivotally mounted to said arm carrier and movablebetween rst and second pivoted positions upon movement of said carrier,and including lock means, cooperable with lock means on said arm carrierin the rst pivoted position,

cam means on said frame,

cam means on said second grasping arm engageable with said frame cammeans upon movement of said arm carrier to move said second arm to saidsecond pivoted position, said ca-m means including means to lock saidsecond arm in said second pivoted position,

and means on said second arm lock means engageable with means on saidframe, upon movement of said carrier, to release and lock said lockmeans.

2. The invention according to -claim 1 wherein said lock means holdssaid second arm against one of clockwise and counterclockwise pivotingmovement,

and stop means on said carrier and engageable with said second arm,holding said second arm against the other of clockwise andcounterclockwise pivoting movement.

3. The invention according to claim 1 including stop means on said armcarrier and engageable with said second grasping arm, and in combinationwith said rst lock mean-s, holding said second arm against pivotingmovement.

4. The invention according to claim 1 wherein said lock means compriseslever means pivoted to one of said `arm and said arm carrier, and latchpin means on the other of said arm and said arm carrier,

said pivoted lever means including latch notch means receiving saidlat-ch pin means in locking relation when the several parts swing to aposition for such action to take place,

and means normally biasing said latch lever means toward said latch pinmeans.

5. The invention according to claim 4 wherein said last recitedengageable Imeans on said second arm comprises a cam surface on saidlever means and engageable with said frame cam means upon movement ofsaid carrier.

6. The invention according to claim 1 wherein said cam means on saidframe is one of cam track and cam follower means; and, said cam means onsaid second grasping arm is the other of a cam track and cam followermeans.

7. The invention according to claim 6 wherein said cam means on saidframe is a cam track means and wherein said cam means on said second armis a cam follower means.

8 8. The invention according to claim 1 wherein each of said first andsecond grasping arms is provided with a pivoted grasping jaw, movableinto conformed relation to the surface of a Iroll on contact, and meanslnormally biasing said jaws to a neutral position.

9. In a roll clamp of the class described:

a frame having irst linear guide means thereon,

a first clamp arm carried by said first linear guide means and means forlinearly moving said arm relative to said guide means,

second linear guide means on said frame, an arm car rier, and means forlinearly moving said arm means along said second linear guide means, asecond clamping arm pivotally mounted to said arm carrier and movablebetween first and second pivoted positions corresponding respectivey topositions for clamping large and small rolls of sheet material,

means for locking said second clamping arm in said first pivotedposition against clockwise or counterclockwise movement,

means for moving said second clamping arm to said second pivotedposition,

and second means for locking said second clamp arm in said secondpivoted position against clockwise and counterclockwise pivotingmovement.

References Cited UNITED STATES PATENTS 3,127,209 3/1964 Faust et al.294-88 3,198,568 8/1965 Mindrurn 294-88 3,252,609 5/1966 'Ellis 294-88ANDRES H. NIELSEN, Primary Examiner.

U.S. Cl. X.R. 214-653; 294-88

